It is well-known in the art to mix two or more materials to form a uniform flowable liquid. One prior art apparatus for accomplishing such mixing, shown in the patent to S. L. Goodchild, U.S. Pat No. 2,502,563, uses two oppositely rotating intermeshed rotors acting in a chamber wherein the materials being mixed are pumped into the chamber and allowed to flow laterally along the length of the rotors as they are mixed. Another mixing technique, shown in the patent to C.H. Goodwin, U.S. Pat. No. 3,142,476, incorporates a large sun gear surrounded by a series of planetary gears which intermesh with and rotate upon rotation of the sun gear. The fluid is mixed by movement past the plurality of sun gears and their engagement with the planetary gear, such movement being counter to the movement of the teeth of the sun gear.
Another mixing apparatus is shown in the patent to S.G. Bauer, U.S. Pat. No. 2,116,380, wherein a gear pump is constructed with sufficient clearance between the casing and the teeth of the gears to provide a definite leakage path for the material under treatment from the outlet end toward the inlet end of the pump with a exhaust valve designed to ensure return flow of a substantial portion of the mass along the leakage path. Such pump provides for the recirculation of fluid between the teeth of the gears and the casing to effect mixing of the liquids.
A material mixing and treating apparatus is shown in the patent to A. Albers, U.S. Pat. No. 4,605,309, wherein a roller mill with the two rotatable rollers of a roller mill rotate at different speeds relative to one another. The external surfaces of the rollers have grooved portions with the transition regions between such surface in each such groove being sharp-edged. The grooves are inclinedly disposed at an acute angle relative to the roll axis with the grooves on the first roll having an opposite hand to the grooves on the second roll. The material enters at one end of the rollers and is discharged at the opposite end after having traversed a path along the longitudinal axis of the rolls. The material is subjected to a saw-like or chopping action resulting in an intense shearing heat being produced.
Although these prior devices have accomplished their objective, that is, the mixing of two or more fluid components, the apparatus shown in the patents to Bauer, Goodchild, and Goodwin are not designed to materially alter the components being mixed and therefore do not improve the rheological or physical properties of the material. The apparatus shown in the patent to Albers, while designed to effect material shearing, accomplishes such shearing only by having spiral grooves which must form sharp edges for effecting such shearing action and by the rotation of the rolls at different speeds.
Thus, a need exists, and has existed for a substantial time, for a processing apparatus which not only mixes material, but improves the rheological and material properties, without the need to add heat to the system or to materially increase the temperature of the bulk fluids being processed.